Development of an automatic control two-dimensional tactile patterns delivery device using in high magnetic field and investigation on human characteristics of tactile shape discrimination

Abstract

In present study, we developed a novel automatic tactile patterns delivery device that is capable of perform the tactile cognitive and neuroimaging procedures. It can serve to determining the underlying central neural mechanisms that contribute to tactile shape discrimination. The primary device consists of a finger movement orbit control unit (FCU), a disk for tactile pattern delivery (DTD), and ultrasonic motor and force sensor unit (UFU). Using energy from two ultrasonic motors to turn the DTD and FCU, the pressure applied by the fingertip can be measure with force sensor unit. The positioning of the patterns and the finger movement of subjects are controlled by a computer. To evaluate the performance of the device, we conducted three basic function tests and a functional Magnetic Resonance Imaging (fMRI) capability test. The results indicated that the device can record reliable data and control the tactile pattern position precisely. There was no measurable modification of the signal-to-noise ratio in the high magnetic field (MRI) when operated with the main device. Finally, twenty young subjects consented to participate in the active and passive shape discrimination tasks. The results support our hypothesis that the performance of active touch was greater than passive touch, but the tendency depend on the similarity value of the tactile shape stimulus.